Min length for tailpiece?

Does the tailpiece for a kitchen sink need to be a minimum length before it enters the p-trap? Can it be as short as 3" without causing any problems? I would like to install the drain and p-trap as high as possible to open up the area underneath the kitchen sink.

Advertisement

Min length for tailpiece?

There really isn't a minimum length that I know of but a couple of things to consider:
A short tailpiece will eliminate any future installation of a disposal unit or a deeper sink.
If this is a renovation project and the tee or 90 is already roughed in inside the wall at the back of the cabinet, you must plumb your p trap at that elevation. If you don't your trap will not function properly.

Min length for tailpiece?

I am bldg a new house and have always wondered why the drains are so low - I assume it is because putting them at a standard height doesn't take any thought and therefore is quick and easy because they will always work and not cause any installation problems regardless of the sink purchased.

Good point about the disposal. However, my wife hates them - and believe it or not seldom changes her mind about such things - even the arrangement of furniture.

Min length for tailpiece?

between undermount sinks and sinks being about 3 inches deeper then they were 30 years ago and garbage disposals you need the drain low to accommodate any scenario that might come up. if you are a plumber and had to try and hook a sink up with the drain a couple of inches too high cause they bought a deeper sink you would rough the drain in lower also. standard rough in height for a kitchen sink used to be 16 inches off the floor.

Min length for tailpiece?

Min length for tailpiece?

for kitchens 15 inches above finished floor should work, in bathrooms 18 was the norm years ago. If you are using a vessel sink the drain could be much higher but then you could not put a regular vanity without opening the wall and lowering the drain. countertop height has gotten higher also. Many vanities are 36 inches to the top(same as kitchens) where they used to be 30 inches to the top of the counter.